What is the name of the conflict between where the eyes focus and where they converge in VR?

Vergence-accommodation conflict is the conflict between where the eyes converge and where they focus in virtual reality. In ordinary vision, these two responses normally work together at the same physical distance.

A conventional stereoscopic headset presents separate images to the left and right eyes to create a sense of depth. The eyes may converge on a virtual object that appears several metres away, while the display optics require them to accommodate, or focus, at a fixed screen distance. This mismatch can contribute to visual discomfort, fatigue, and difficulty sustaining focus.

The problem is one reason researchers investigate varifocal, multifocal, and light-field displays. These systems attempt to provide more natural focus cues instead of presenting every virtual object on a single optical focal plane. Vergence-accommodation conflict is therefore an optics issue, not the same thing as ordinary image distortion or motion sickness.